A good part of the web sites currently existing on the Internet are solely financed by the income obtained by inserting advertising banners (normally Flash animations or images) of other advertisers on their web pages, next to the fundamental contents of said sites.
The mentioned advertising income is obtained in two ways:
On one hand, by the total audience of said banners. This variable is measured by counting the number of times the advertising banners are downloaded in the customers' browsers. Said amount is easy to determine given that it equals the number of direct requests of such banners from the customers' browsers, which banners are normally stored in specific advertising servers normally different from those of the web pages in which they are inserted.
On the other hand, by the explicit interest of the customers in such banners. This parameter is measured by counting the number of times the customers request more information about the advertisement in question by clicking with the cursor on the banner associated to said advertisement. This number is usually much lower than the previous one because it usually depends on the motivation of the customer to click, on the appeal of the advertising banner, etc.
The comparison between the number of banner downloads and the number of times the customers see said banners in the PC world is due to the fact that the banners are usually placed in the pages such that the customer can see them upon downloading the page without needing to scroll. Downloading therefore implies displaying the banner in PC environments.
Despite the foregoing, in the past few months mobile devices (mobile terminals, PDAs, etc.) are beginning to come out which allow browsing the Internet without the user needing to have a PC. Given that the size of the screen of such mobile devices is much smaller than that of a normal PC, several technologies for displaying the contents on small screens have come out in order to facilitate displaying web pages:
On one hand, the most basic and evident technology is not to do anything with the content such that if a page takes up the size of a conventional PC screen, if a terminal browses through the same page it must scroll both horizontally and vertically to see the entire page. This option is the least used due to its poor usability for accessing texts.
An improvement to the foregoing is the technology which the new Nokia® S60 R3 terminals implement, incorporating a new browser based on the Apple® Safari browser which, although forcing the subscriber to scroll horizontally to see the entire page, allows such subscriber to read the texts of the page without needing to scroll, i.e. adapting the paragraphs of the text to the width of the screen of the terminal.
A variation of the previous solutions consists of completely reformatting the web page completely displaying it as a column in the terminal, always preventing the need to scroll horizontally. Solutions such as Opera Mini or Blackberry® implement this variation, which generally (although not mandatorily) requires the existence of a specific server for reformatting the pages.
In all the previous cases and due to the size of the screen it is impossible to ensure that an advertising banner downloaded in the browser is finally viewed by the customer, nevertheless the mentioned advertisement measuring systems usually count the banners downloaded in mobiles as advertising hits in customers.
It is therefore necessary to find a way to ensure advertising servers that a banner of a web page has not only been downloaded in a browser of a mobile terminal but also viewed by the end customer.
Although languages such as JavaScript allow certain control of the position of the objects (essentially their ends) on the screen, managing said position when the subscriber scrolls becomes more complicated (impossible in some cases). Likewise, the page reformatting which some solutions such as those previously described carry out, usually makes treating such position in JavaScript impossible, for which reason it is necessary that the browser itself is what determines whether or not the object has been displayed.
It is known that abbreviations and acronyms are frequently used in the field of computer mobile telephony and web browsers. A glossary of terms and acronyms used through the present specification is provided below:                HTML: HyperText Markup Language        HTTP: Hypertext Transfer Protocol        IP: Internet Protocol        URL: Universal Resource Locator        W3C: World Wide Web Consortium        